不同供磷水平对辣椒根系形态和根际特征的影响

以辣椒品种线椒王为试验材料，采用盆栽方式，通过分析不同施磷水平下辣椒根系形态和根系生理的变化，探究辣 椒磷高效利用的主要根系及根际过程。结果表明，辣椒地上部和根系生物量随供磷水平的增加呈现先增加后下降的趋势，整 株磷浓度以及整株磷累积量呈增加趋势。随供磷水平增加，根系总根长呈先增加后下降趋势，根系平均直径、根冠比呈逐渐 降低趋势；辣椒根系菌根侵染率和土壤酸性磷酸酶活性呈现先增加后下降的趋势。相关分析结果表明，土壤有效磷浓度和整 株磷浓度与根系平均直径、菌根侵染率呈极显著负相关，与总根长可用一元二次方程拟合，表明辣椒根系适应低磷的根际特 征可能是通过增加根系生物量及总根长，同时降低根系平均直径来实现的。     

F-box domain is involved in regulating the proliferation of MCF-7 cells by FBXO39 protein

AIM: To investigate the effect of F-box domain on the regulation of MCF-7 cell proliferation by FBXO39 protein. METHODS: The effect of F-box domain on the localization of FBXO39 protein in the MCF-7 cells was investigated. MCF-7 cell cDNA library was used as the template resource. The full-length cDNA sequence of FBXO39 was amplified by PCR method and subcloned into eukaryotic expression vector pEGFP-C2. The pEGFP-FBXO39ΔF (F-box domain deletion mutation) plasmid was successfully constructed with the template resource of pEGFP-FBXO39 plasmid. The recombinant plasmids were transfected into the MCF-7 cells, and then the expression of FBXO39 and FBXO39ΔF were determined by Western blot. The cellular localization of FBXO39 and FBXO39ΔF were observed by confocal microscopy. The localization of endogenous FBXO39 in the MCF-7 cells was detected by immunofluorescence staining. In addition, MTT and EdU assays were used to measure the cell proliferation, flow cytometry was used to measure the cell cycle distribution, and immunohistochemical staining was used to observe the expression of FBXO39 in the breast cancer and para-carcinoma tissues. RESULTS: The eukaryotic expression vector pEGFP-FBXO39 and pEGFP-FBXO39ΔF were constructed successfully. F-box domain had no effect on the cell localization of FBXO39. FBXO39 promoted MCF-7 cell proliferation but FBXO39ΔF did not. FBXO39 was highly expressed in the breast cancer tissues. CONCLUSION: F-box domain had no effect on the cellular localization of FBXO39 protein. However, it plays an important role in the biological function of FBXO39. FBXO39 may be related to breast cancer tumorigenesis.     

Challenges for the sustainable use of water and land resources under a changing climate and increasing salinization in the Jizzakh irrigation zone of Uzbekistan

Jizzakh Province in Uzbekistan is one of the largest irrigated areas in Central Asia without natural drainage.In combination with aridity,climate change and extensive irrigation practices,this has led to the widespread salinization of agricultural land.The aim of this study was to identify opportunities to improve the reclamation status of the irrigated area and how best to effectively use the water resources in Jizzakh Province based on investigations conducted between 1995 and 2016.A database of field measurements of groundwater levels,mineralization and soil salinity conducted by the provincial Hydro-Geological Reclamation Expeditions was used in the study.The total groundwater mineralization was determined using a portable electric conductometer(Progress 1T)and the chloride concentration was determined using the Mohr method.The soil salinity analyses were conducted by applying two different methods:(1)the extraction and assessment of the soluble salt content,and(2)using an SM-138 conductivity sensor applied to a 1:1 mixture of soil sample and water.The analyses of the monitoring results and the salt balance in the"irrigation water–soil–drainage water"system clearly demonstrated that the condition of the irrigated land in the province was not significantly improved.Under these conditions,the stability of crop yields is achieved mainly through the use of large volumes of fertilizer.However,excess amounts of mineral fertilizers can also cause the salinization of soils.The average groundwater salinization value in most of the irrigated land(75.3%)fluctuated between 1.1 and 5.0 g/L,while the values were less than 1.0 g/L in 13.1%of the land and in the range of 5.1–10.0 g/L in 10.5%of the land.During the period of 1995–2016 the salinization level of the irrigated land in Jizzakh Province increased slightly and the area could be divided into the following classes:no salinity(17.7%of the total area),low salinity(51.3%),moderate salinity(29.0%),and high salinity(2.0%).Detailed studies of the salt balance in irrigated land,the impact of climate change,increased fertilizer use,and repeated remediation leaching on the groundwater level and mineralization should be conducted in the future,due to the possibility of accelerated salinization,fertility decline,and reduced yields of agricultural crops.     

山葡萄VaCIPK18原核表达与多克隆抗体制备

类钙调磷酸酶B亚基蛋白(CBLs)互作蛋白(CIPKs) 作为类丝氨酸/苏氨酸蛋白激酶,在植物响应非生物胁迫信号转导中起着重要作用。基于前期山葡萄响应低温胁迫转录组测序结果,发现低温胁迫引发的早期伤害及感知阶段的激酶基因中涉及CBL-CIPK 信号通路的VaCIPK18表达显著上调。为进一步研究山葡萄(Vitis amurensis)VaCIPK18激酶参与低温胁迫的功能,采用同源克隆获得了VaCIPK18基因,其开放阅读框为1 320 bp,编码439个氨基酸。基于对VaCIPK18蛋白生物信息学分析,获取胞外结构域中抗原表位丰富的肽段,并将其C端调控结构域(230~439 aa)构建到原核表达载体pET28a-SUMO。将重组表达载体转化至大肠杆菌(E. coli Rosetta)中,经0.8 mmol·L^-1 IPTG、37℃诱导4 h表达出大小为42 kDa的包涵体蛋白。将重组蛋白作为抗原免疫日本大耳白兔,获得anti-VaCIPK18多克隆抗体,经检测具有高效价及特异性。Western Blot结果表明,该抗体可以与葡萄内源CIPK18特异性结合,且在50 kDa位置出现与预期一致的条带。同时,CIPK18在低温胁迫后葡萄叶片中蛋白表达水平与室温下相一致,但两种状态下均存在可能的磷酸化与泛素化修饰现象。本研究结果为进一步探究VaCIPK18的蛋白定位、表达及其功能奠定了基础。     

Partial fishmeal replacement by mussel meal or meat and bone meal in low‐fishmeal diets for juvenile Ussuri catfish (Pseudobagrus ussuriensis): Growth,digestibility, antioxidant capacity and IGF‐I gene expression

This study evaluated the effects of replacing fishmeal with mussel meal or meat and bone meal in low‐FM diet on growth performance, body composition, digestibility, antioxidant capacity and IGF‐I gene expression in juvenile Ussuri catfish (Pseudobagrus ussuriensis). The results showed that no significant changes in SGR, FE and PER were observed between MM₄₀ and LFM groups, but significantly reduced result was found in MBM₄₀ group. MM₄₀ group showed the higher ADC of lipid (93.30%) and lipase activity (95.00 U/gprot) than LFM group (90.97%; 70.18 U/gprot). MM₄₀ or MBM₄₀ diets led to significant reduction of SOD and CAT activities. MM₄₀ group showed significantly higher MDA level (5.84 nmol/mg) than LFM group (4.73 nmol/mg). The activities of LZM decreased significantly in MM₄₀ and MBM₄₀ groups compared with LFM group. MM₄₀ and MBM₄₀ groups showed no significant difference in hepatic IGF‐I gene expression levels compared with LFM group. The findings demonstrated that MM could substitute 400 g/kg of FM in low‐FM diet for Ussuri catfish without influencing the growth, but to some extent, spontaneous oxidative stress and immune damage could occur; when 400 g/kg of FM was replaced by MBM, significantly negative effects were observed on growth, antioxidant capacity and non‐specific immune response of Ussuri catfish.     

Karanj protein isolate prepared from karanj seed cake: Effect on growth,body composition and physiometabolic responses in Labeo rohita fingerlings

A protein isolate was prepared from karanj seed (KPI) with 921.2 g protein/kg seed, which contained a negligible amount of anti‐nutritional factors and a balanced amino acid composition, especially rich in methionine. For 60‐day feeding trial, five isonitrogenous (300 g/kg CP) and isocaloric (15 MJ DE/kg) diets were formulated by replacing soybean protein isolate (SPI) on protein equivalent basis, KPI‐0 (control, 0 g/kg KPI); KPI‐25 (replacing 250 g/kg SPI protein with KPI); KPI‐50 (replacing 500 g/kg SPI protein with KPI); KPI‐75 (replacing 750 g/kg SPI protein with KPI) and KPI‐100 (replacing 1,000 g/kg SPI protein with KPI) for the feeding of L. rohita. The weight gain percentage, specific growth rate, feed conversion ratio and protein efficiency ratio were not significantly (p > .05) varied among the KPI fed and control groups. A significantly higher hepatosomatic index was recorded in the control and KPI‐25 groups compared with other groups. The whole‐body compositions, except ether extract, did not differ significantly (p > .05) among the groups. Digestive (amylase, protease, lipase and alkaline phosphatase) and metabolic enzyme activities (hexokinase, transaminases and lactate dehydrogenase) and glycogen stores were not significantly affected, whereas intestinal alkaline phosphatase differed significantly (p < .05). The RNA–DNA ratio was significantly (p < .05) higher in the KPI‐75 group. Thus, the study revealed that KPI can completely replace SPI protein at 191 g/kg inclusion level in the diets of L. rohita fingerlings.     

Effects of dietary protein on growth performance,nutrient utilization,digestive enzymes and physiological status of grey mullet,Mugil cephalus L. fingerlings reared in inland saline water

A 60 days feeding trial was conducted to illustrate the effect of graded levels of protein on the growth and metabolic enzymes of grey mullet (Mugil cephalus L.) fingerlings reared in inland saline water (ISW). Six isoenergetic (16 MJ/kg) and isolipidic (60 g/kg) diets containing 240, 260, 280, 300, 320 and 340 g crude protein (CP)/kg diet were formulated and fed to triplicate. Weight gain %, specific growth rate, protein utilizing efficiency, feed efficiency and RNA:DNA ratio were significantly higher (p < .05) in 320 and 300 g CP/kg diets. Fish fed with 240 g CP/kg diet showed significantly higher (p < .05) feed intake, whole‐body lipid content, hepatosomatic index value and liver glycogen content. Transaminase enzymes and malate dehydrogenase activities were elevated in fish fed 340 g CP/kg diet. Protease activity increased with increasing dietary CP level, but amylase activities showed an inverse relationship. No significant (p > .05) variations were observed for lactate dehydrogenase, oxidative stress enzymes, blood parameters and serum osmolality among all the treatment groups, but red blood cell count increases with increasing dietary CP levels. Based on the results, feeding dietary protein level of 300 g CP/kg is economically viable for rearing of grey mullet in ISW.     

Nutritional evaluation of two marine microalgae as feedstock for aquafeed

Using microalgae for animal nutrition provides an economically viable route for microalgae‐based technological innovation, especially in combination with CO₂ fixation given current global warming. However, this technology still lacks sufficient evaluation for screening microalgae for specific animals; meanwhile, current studies show some prejudice regarding ‘essential’ or ‘non‐essential’ ingredients. The results show that Dunaliella salina and Nannochloropsis salina were able to accumulate high protein (30%–57%) and lipid (20%–46%) content without affecting the performance of CO₂ fixation, which reached 0.28 and 0.23 g L^?1 day^?1 respectively. Both species exhibited high quality of lipids and proteins for Penaeus monodon based on the profiling. The essential fatty acid indexes (EFAI) for N. salina and D. salina were 3.81 and 9.02 respectively. Butyric acid was found to be present in both D. salina (12.03%) and N. salina (4.87%) based on the total fatty acids (FAs). The essential amino acid indexes (EAAI) for D. salina and N. salina were 2.23 and 1.29 respectively. Arginine was the most abundant essential amino acid (EAA) in both D. salina (10.83%) and N. salina (13.35%) on the basis of total amino acids (AAs). This study comprehensively compares the nutritional quality of the two commercial marine microalgae of D. salina and N. salina with the potential to be used as sustainable sources of lipids and proteins to reduce or even replace the traditional fish oil and fish meal in aquafeeds.     

Partial replacement of fishmeal with Clostridium autoethanogenum single‐cell protein in the diet for juvenile black sea bream (Acanthopagrus schlegelii)

Clostridium autoethanogenum protein (CAP) is a single‐cell protein derived from ethanol production and may have potential to become a substitute for fishmeal in aquafeeds. A 70‐day feeding trial was conducted with black sea bream (Acanthopagrus schlegelii) (mean initial weight 6.03 ± 0.09 g) to evaluate partial replacement of fishmeal with CAP in diets. Seven isonitrogenous and isoenergetic diets were formulated with graded levels of CAP (0, 4.85, 9.70, 14.55, 19.40, 38.80 and 58.20%) to replace fishmeal. The inclusion of CAP at all dietary levels tested did not significantly affect the growth performance (p > .05). Fish fed the CAP58.20% diet showed a significantly lower feeding rate, with significantly higher protein efficiency ratio and feed efficiency ratio compared with fish fed the other diets (p < .05). No statistical differences were found in dorsal muscle and whole‐body compositions. Total superoxide dismutase in serum of fish fed CAP58.20% diet was significantly lower compared with that of the control. Malondialdehyde, catalase, total antioxidant capacity and digestive enzyme activities revealed no significant differences among dietary treatments. Phosphorus retention efficiency significantly increased, and phosphorus discharge showed a downward trend with increasing CAP inclusion levels. In conclusion, the results indicated that CAP is a safe and effective alternative protein source, which can replace fishmeal in the diet of black sea bream up to 58.20%, without adverse effects on growth performance, antioxidation and digestive enzyme activity. This study has shown the potential of converting industrial waste into a high protein feed ingredient for aquafeeds.     

三种酶制备牡蛎蛋白水解物的抗氧化活性和功能特性分析

目的：比较分析木瓜蛋白酶、胃蛋白酶和胰蛋白酶三种不同酶水解牡蛎获得的蛋白产物抗氧化活性和功能特性。方法：采用木瓜蛋白酶、胃蛋白酶和胰蛋白酶三种不同酶水解牡蛎蛋白获得水解物,并分别测定它们的在不同pH下的溶解度、乳化性以及不同浓度水解物的还原能力、DPPH自由基清除率和Fe^{2 +}螯合能力。结果：表明三种酶水解物都有较高的溶解度(p＜0.01),胰蛋白酶产生的水解物溶解高度达94.8％(p＜0.05)；水解物溶解度和乳化活性指数在pH4显著降低(p＜0.05)。牡蛎蛋白质水解产物的还原能力、DPPH自由基清除能力和金属螯合活性随浓度的增加而增强,其中胰蛋白酶和胃蛋白酶抗氧化能力较强(p＜0.01)。结论：三种蛋白酶水解牡蛎蛋白可获得抗氧化活性强、溶解度高的水解物,并受浓度和pH的影响,它们的水解物可作为一种潜在的抗氧化功能多肽利用。